U.S. patent number 10,103,130 [Application Number 15/455,236] was granted by the patent office on 2018-10-16 for led module.
This patent grant is currently assigned to Rohm Co., Ltd.. The grantee listed for this patent is ROHM CO., LTD.. Invention is credited to Masahiko Kobayakawa, Takashi Moriguchi.
United States Patent |
10,103,130 |
Kobayakawa , et al. |
October 16, 2018 |
LED module
Abstract
An LED module includes a substrate, one or more LED chips
supported by a main surface of the substrate, and wirings. The
substrate has one or more through holes penetrating from the main
surface to a rear surface. The wirings are formed on the substrate
and make electrical conduction with the LED chips. The wirings
include pads which are formed on the main surface and make
electrical conduction with the LED chips, rear surface electrodes
which are formed on the rear surface, and through wirings which
make electrical conduction between the pads and the rear surface
electrodes and are formed on the inner sides of the through
holes.
Inventors: |
Kobayakawa; Masahiko (Kyoto,
JP), Moriguchi; Takashi (Kyoto, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
ROHM CO., LTD. |
Kyoto |
N/A |
JP |
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Assignee: |
Rohm Co., Ltd. (Kyoto,
JP)
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Family
ID: |
46636219 |
Appl.
No.: |
15/455,236 |
Filed: |
March 10, 2017 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20170186735 A1 |
Jun 29, 2017 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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14703169 |
May 4, 2015 |
9613935 |
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13369571 |
May 26, 2015 |
9041016 |
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Foreign Application Priority Data
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Feb 10, 2011 [JP] |
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2011-026857 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L
33/62 (20130101); H01L 25/0753 (20130101); H01L
33/54 (20130101); H01L 33/486 (20130101); H01L
33/60 (20130101); H05K 999/99 (20130101); H01L
2224/48227 (20130101); H01L 2224/48091 (20130101); H01L
2224/48091 (20130101); H01L 2924/00014 (20130101) |
Current International
Class: |
H01L
33/08 (20100101); H01L 25/075 (20060101); H01L
33/48 (20100101); H01L 33/62 (20100101); H01L
33/54 (20100101); H01L 33/18 (20100101); H01L
33/60 (20100101) |
Field of
Search: |
;257/13,79-103,918,40,642-643,759,E51.018-E51.022,E33.054,E25.028,E25.032,E31.058,E31.063,E31.115,E27.133-E27.139
;438/22,26,27,122,118 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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101562178 |
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Oct 2009 |
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CN |
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101743647 |
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Jun 2010 |
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CN |
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2004-253711 |
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Sep 2004 |
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JP |
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2006-024794 |
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Jan 2006 |
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JP |
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Other References
Chinese Office Action, issued in the corresponding Chinese
Application No. 201210029823.8, dated Sep. 2, 2015, 15 pages. cited
by applicant.
|
Primary Examiner: Rahman; Moin
Attorney, Agent or Firm: Hamre, Schumann, Mueller &
Larson, P.C.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a Continuation of application Ser. No.
14/703,169, filed May 4, 2015, which is a Division of application
Ser. No. 13/369,571, filed Feb. 9, 2012 (now U.S. Pat. No.
9,041,016, issued May 26, 2015), which is based upon and claims the
benefit of priority from Japanese Patent Application No.
2011-26857, filed on Feb. 10, 2011, the entire contents of which
are incorporated herein by reference.
Claims
What is claimed is:
1. A light emitting device module comprising: a support part having
a rectangular shape, and including a first pair of sides facing
each other in a plan view, and a second pair of sides connected to
end portions of the first pair of sides and extending to a
direction perpendicular to the first pair of sides; a first
electrode, a second electrode, a third electrode, and a fourth
electrode formed on a surface of the support part and being spaced
apart from each other, each surface of the first, second, third,
and fourth electrodes being exposed from the support part, a first
light emitting element disposed on a surface of the first
electrode, a second light emitting element disposed on a surface of
the second electrode, a third light emitting element disposed on a
surface of the third electrode, a first wire connecting a surface
of the first light emitting element and the fourth electrode, and a
second wire connecting a surface of the second light emitting
element and the fourth electrode, wherein the first light emitting
element, the second light emitting element, the third light
emitting element, and the fourth electrode are formed to overlap in
a first direction which extends in a same direction of the first
pair of sides, the second light emitting element is disposed on one
side of the first pair of sides, the second electrode includes a
first region located closer to one side of the first pair of sides
than the other side of the first pair of sides, an exposed area of
the second electrode is larger on a side that the first region is
located, in a plan view, and the third electrode includes a second
region located closer to one side of the first pair of sides than
the other side of the first pair of sides, an exposed area of the
third electrode is larger on a side that the second region is
located, in a plan view.
2. The light emitting device module of claim 1, wherein the first
light emitting element is disposed within outer edges of the first
electrode, the second light emitting element is disposed within
outer edges of the second electrode, and the third light emitting
element is disposed within outer edges of the third electrode.
3. The light emitting device module of claim 1, wherein one of a
red light, a blue light, or a green light is emitted by one of the
first light emitting element, the second light emitting element, or
the third light emitting element.
4. The light emitting device module of claim 1, wherein the first
wire extends from the first light emitting element to a portion of
the fourth electrode formed closer to one side of the first pair of
sides.
5. The light emitting device module of claim 1, wherein each of the
first, second, and third electrodes include at least one curved
portion.
6. The light emitting device module of claim 1, further comprising
a reflector surrounding the support part and having a rectangular
shape in a plan view.
7. The light emitting device module of claim 1, wherein each side
of the first, second, and third light emitting elements either
extends in a same direction of the first pair of sides or extends
in a perpendicular direction of the first pair of sides.
8. The light emitting device module of claim 1, further comprising
a fifth electrode formed on the surface of the support part and
spaced apart from the first, second third and fourth electrodes,
and formed to be on one side of the second pair of sides opposite
from the fourth electrode.
9. The light emitting device module of claim 8, further comprising
a third wire connecting the third light emitting element and the
fifth electrode.
10. The light emitting device module of claim 9, wherein the third
wire extends from the third light emitting element to a portion of
the fifth electrode formed closer to one side of the first pair of
sides.
Description
TECHNICAL FIELD
The present disclosure relates to an LED module incorporating LED
chips, and more particularly, a so-called side view type LED
module.
BACKGROUND
FIG. 14 shows a conventional LED module in a related art. As shown
in FIG. 14, an LED module 900 has a structure where three LED chips
931, 932 and 933 are mounted on a long rectangular substrate 910.
The substrate 910 is formed with a plurality of electrodes 921,
922, 923 and 924. The electrodes 921, 922 and 923 are respectively
die-bonded with LED chips 931, 932 and 933. The electrode 924 is a
so-called common electrode which makes electrical conduction with
the LED chips 931, 932 and 933 via a wire. The three LED chips 931,
932 and 933 are surrounded by a case 950. The case 950 is made of
frame-like opaque resin material and its inner space is filled with
light transmitting resin (not shown). The LED module 900 is
configured as a so-called side view type LED module which is
mounted on a circuit board, with a lower surface (in the drawing)
extending in a longitudinal direction of the substrate 910 as a
mounting surface. The LED chips 931, 932 and 933 emit red, green
and blue light, respectively. The LED module 900 is configured to
emit white light by mixing the light from these LED chips 931, 932
and 933.
However, there are ever increasing requirements for reducing the
size of the LED module 900. For example, in order to restrict a
projecting height of the LED module 900 from the circuit board on
which the LED module 900 is mounted, there is a need to make the
substrate 910 more compact. This reduces the space for mounting the
LED chips 931, 932 and 933. To mount the LED chips 931, 932 and
933, additional space, in addition to the space needed for the LED
chips 931, 932 and 933, is needed for wires connected to these LED
chips and a portion of the common electrode 924 to which these
wires are connected. In addition, the area ratio of the electrodes
922 and 923 to the substrate 910 is not small. Thus, this makes it
difficult to achieve a compact substrate 910.
SUMMARY
The present disclosure provides some embodiments of a side view
type LED module capable of being compact.
According to one aspect of the present disclosure, there is
provided an LED module including a substrate, one or more LED chips
and wirings. The substrate includes rectangular main and rear
surfaces which are in opposite to each other, and a bottom surface
which is a mounting surface and connects long sides of the main and
rear surfaces. The substrate includes one or more through holes
penetrating from the main surface to the rear surface. One or more
LED chips are supported by the main surface of the substrate. The
wirings are formed on the substrate and make electrical conduction
with the LED chips. The wirings include pads, rear surface
electrodes and through wirings. The pads are formed on the main
surface and make electrical conduction with the LED chips. The rear
surface electrodes are formed on the rear surface. The through
wirings make electrical conduction between the pads and the rear
surface electrodes and are formed on the inner sides of the through
holes.
In one embodiment, the wirings expose the entirety of the bottom
surface of the substrate.
In another embodiment, three spaced LED chips are arranged along a
longitudinal direction of the main surface.
In another embodiment, the substrate has two through holes and the
wirings include two through wirings.
In another embodiment, the two through wirings deviate from the LED
chips making electrical conduction with the two through wirings in
the longitudinal direction and overlap with the LED chips in a
transverse direction of the main surface.
In another embodiment, the rear surface electrodes respectively
include two individual electrodes making electrical conduction with
the through wirings.
In another embodiment, the two through holes are disposed in a
portion in the substrate opposite to the bottom surface in the
transverse direction.
In another embodiment, the substrate has a pair of lateral sides
and two corner grooves. A pair of lateral sides connects the main
surface and the rear surface in both ends of the substrate in the
longitudinal direction. The two corner grooves are interposed
between the lateral sides and the bottom surface, and reach the
main surface and the rear surface in a thickness direction of the
substrate. Further, the wirings include two corner groove wirings
formed on the inner sides of the two corner grooves.
In another embodiment, one of the two corner groove wirings makes
electrical conduction with a plurality of LED chips and the rear
surface electrodes include an end common electrode connected to the
corner groove wiring.
In another embodiment, the other of the two corner groove wirings
makes electrical conduction with one of the plurality of LED chips
and the rear surface electrodes include an end individual electrode
connected to the corner groove wiring.
In another embodiment, the corner grooves have a quadrant-circular
section.
In another embodiment, the wirings include a main surface
interconnection wiring, a branch-like wiring and a wire. The main
surface interconnection wiring is placed near the bottom surface in
the transverse direction with respect to the LED chips. The main
surface interconnection wiring extends in the longitudinal
direction and is connected to the corner groove wiring making
electrical conduction with the end common electrode. The
branch-like wiring extends from the main surface interconnection
wiring between two LED chips. With this configuration, the wire
connects the two LED chips and the branch-like wiring.
In another embodiment, the LED module further includes an
insulating film which is provided near the rear surface and covers
at least a portion of the individual electrodes and the through
holes.
In another embodiment, the LED module further includes light
transmitting resin covering the three LED chips.
In another embodiment, the light transmitting resin has a
trapezoidal section perpendicular to the transverse direction.
In another embodiment, the light transmitting resin has a
rectangular section perpendicular to the longitudinal
direction.
In another embodiment, the substrate has three through holes and
the wirings include three through wirings.
In another embodiment, the three through wirings deviate from the
LED chips making electrical conduction with the three through
wirings in the transverse direction and overlap with the LED chips
in a longitudinal direction of the main surface.
In another embodiment, one of the three through wirings making
electrical conduction with one of the three LED chips inserted
between the other two LED chips in the longitudinal direction is
placed in a position in the transverse direction which is located
opposite the two remaining through wirings.
In another embodiment, the wirings have die bonding pads as the
pads to which the LED chips are die-bonded, and the die bonding
pads overlap with the through holes when viewed in the thickness
direction of the substrate.
In another embodiment, the rear surface electrodes respectively
include three individual electrodes making electrical conduction
with the through wirings.
In another embodiment, one of the two corner groove wirings makes
electrical conduction with two of the LED chips and the other of
the two corner groove wirings makes electrical conduction with one
of the LED chips. With this configuration, the rear surface
electrodes respectively include two end common electrodes connected
to the corner groove wirings.
In another embodiment, the corner grooves have a quadrant-circular
section.
In another embodiment, the LED module further includes a reflector
and light transmitting resin. The reflector is formed on the main
surface and has a reflecting surface surrounding the three LED
chips. The light transmitting resin fills a region surrounded by
the reflecting surface and covers the three LED chips.
In another embodiment, the wirings include bonding pads as the
pads, and a wire connecting the bonding pads and one of the three
LED chips. One of the three through holes overlaps with the bonding
pads, and one of the three through wirings makes electrical
conduction with the bonding pads.
In another embodiment, the wirings have two die bonding pads as the
pads to which two of the three LED chips are die-bonded, and the
two die bonding pads overlap with the two through holes when viewed
in the thickness direction of the substrate.
In another embodiment, the rear surface electrodes include two
individual electrodes respectively making electrical conduction
with the two die bonding pads via the two through wirings formed in
the two through holes.
In another embodiment, the rear surface electrodes include an end
common electrode and an end individual electrode. The end common
electrode is connected to one of the two corner groove wirings and
makes electrical conduction with the three LED chips. The end
individual electrode is connected to the other of the two corner
groove wirings and makes electrical conduction with one of the
three LED chips.
In another embodiment, the wirings include a rear surface
interconnection wiring which is formed on the rear surface and
connects the end common electrode and the through wirings which
make no electrical conduction with the two individual
electrodes.
Other features and advantages of the present disclosures will be
more apparent from the following detailed description in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view showing main parts of an LED module
according to a first embodiment of the present disclosure.
FIG. 2 is a sectional view taken along line II-II in FIG. 1.
FIG. 3 is a bottom view showing the LED module of FIG. 1.
FIG. 4 is a rear view showing the LED module of FIG. 1.
FIG. 5 is a side view showing the LED module of FIG. 1.
FIG. 6 is a front view showing main parts of an LED module
according to a second embodiment of the present disclosure.
FIG. 7 is a sectional view taken along line VII-VII in FIG. 6.
FIG. 8 is a bottom view showing the LED module of FIG. 6.
FIG. 9 is a rear view showing the LED module of FIG. 6.
FIG. 10 is a front view showing main parts of an LED module
according to a third embodiment of the present disclosure.
FIG. 11 is a sectional view taken along line XI-XI in FIG. 10.
FIG. 12 is a bottom view showing the LED module of FIG. 10.
FIG. 13 is a rear view showing the LED module of FIG. 10.
FIG. 14 is a front view showing main parts of a conventional LED
module.
DETAILED DESCRIPTION
Some embodiments of the present disclosure will now be described in
detail with reference to the drawings.
FIGS. 1 to 5 show an LED module according to a first embodiment of
the present disclosure. In this embodiment, an LED module 101
includes a substrate 200, wirings 300, three LED chips 401, 402 and
403 and light transmitting resin 700. The LED module 101 is formed
as a side view type LED module which is mounted on a circuit board
801 with a posture shown in FIG. 5. In this embodiment, the LED
module 101 has sizes of about 3.0 mm in the x-direction, about 0.43
mm in the y-direction and about 1.3 mm in the z-direction.
The substrate 200 is an insulating substrate made of, for example,
glass epoxy resin and has a rectangular parallelepiped shape with
the x direction as a longitudinal direction, the y direction as a
traverse direction and the z direction as a thickness direction.
The substrate 200 includes a main surface 201, a rear surface 202,
a bottom surface 203 and two lateral sides 204. In addition, the
substrate 200 is formed with two through holes 211 and 212 and two
corner grooves 221 and 222. As shown in FIGS. 1 and 4, the through
holes 211 and 212 are placed in a portion in the substrate 200
opposite the bottom surface 203 in the y direction. In this
embodiment, the substrate 200 has an x-direction dimension of about
3.0 mm, a y-direction dimension of about 0.43 mm and a z-direction
dimension of about 0.5 mm.
The two through holes 211 and 212 penetrate through the substrate
200 in the z direction and extend from the main surface 210 to the
rear surface 202. The corner grooves 221 and 222 are interposed
between the lateral sides 204 and the bottom surface 203 and extend
in the z direction. The corner grooves 221 and 222 extend from the
main surface 201 to the rear surface 202 and have a
quadrant-circular section.
The wirings 300 form paths for supplying power to the three LED
chips 401, 402 and 403 and include die bonding pads 301, 302 and
303, two quadrant-annular portions 321, a main surface
interconnection wiring 322, a branch-like wiring 323, corner groove
wirings 341 and 342, through wirings 351 and 352 and rear surface
electrodes 370. The wirings 300 have a stacked structure of Cu, Ni
and Au plating.
The die bonding pads 301, 302 and 303 are arranged in the x
direction and are bonded with the LED chips 401, 402 and 403,
respectively. The die bonding pads 301 and 302 have a combined
shape of a square portion and a circular portion. Circular portions
of the die bonding pads 301 and 302 are opposite to each other in
the x direction. The die bonding pad 303 has a square portion and a
stripe shape portion extending in the x direction.
The quadrant-annular portions 321 are formed near a portion of the
main surface 201 connected to the corner grooves 221 and 222. The
main surface interconnection wiring 322 has a stripe shape
extending from the quadrant-annular portion 321 formed near the
corner groove 221 in the x direction and is disposed near one end
of the main surface 201 in the y direction. The branch-like wiring
323 extends in the y direction between the die bonding pads 301 and
302 from the middle portion of the main surface interconnection
wiring 322.
The corner groove wires 341 and 342 are formed to cover the inner
sides of the corner grooves 221 and 222 of the substrate 200 and
extend from the main surface 201 to the rear surface 202. The
through wirings 351 and 352 are formed in the inner sides of the
through holes 211 and 212, respectively and have a cylindrical
shape. The through wires 351 and 352 extend from the main surface
201 to the rear surface 202. In this embodiment, the inside of the
through wirings 351 and 352 is filled with resin 602.
The rear surface electrodes 370 are formed on the rear surface 202.
In this embodiment, the rear surface electrodes 370 include
individual electrodes 371 and 372, an end individual electrode 374
and an end common electrode 375. The individual electrodes 371 and
372, the end individual electrode 374 and the end common electrode
375 are arranged in the x direction. The individual electrodes 371
and 372 are interposed between the end individual electrode 374 and
the end common electrode 375. The individual electrode 371 overlaps
with the through hole 211 when viewed in the z direction and is
connected to the through wiring 351. The individual electrode 372
overlaps with the through hole 212 when viewed in the z direction
and is connected to the through wiring 352. The end individual
electrode 374 is disposed near one end of the rear surface 202 and
is connected to the corner groove wiring 342. The end common
electrode 375 is disposed near the other end of the rear surface
202 and is connected to the corner groove wiring 341.
In this embodiment, a plurality of insulting films 601 is formed on
the rear surface 202. These insulating films 601 cover exposed
portions of the rear surface 202 from the rear surface electrodes
370 and portions of the individual electrodes 371 and 372. The
wirings 300 are not formed on the bottom surface 203 and the bottom
surface 203 is entirely exposed. When the LED module 101 is mounted
on the circuit board 801 shown in FIG. 5, a solder fillet 802 is
formed, which is connected to the pads (not shown) of the circuit
board 801 and the individual electrodes 371 and 372. The end
individual electrode 374 and the end common electrode 375 also
include the solder fillet 802 formed therein, with a portion of the
solder fillet 802 filled in a space defined by the end individual
electrode 374 or the end common electrode 375 and the circuit board
801.
The LED chips 401, 402 and 403 are light sources of the LED module
101 and have a stacked structure including, for example, a p-type
semiconductor layer, an n-type semiconductor layer and an active
layer interposed therebetween. The LED chip 401 is die-bonded to
the die bonding pad 301 and emits blue light, for example. The LED
chip 402 is die-bonded to the die bonding pad 302 and emits red
light, for example. The LED chip 403 is die-bonded to the die
bonding pad 303 and emits green light, for example. The LED chips
401 and 402 are connected to the branch-like wiring 323 via wires
500, respectively. The LED chip 403 is connected to the main
surface interconnection wiring 322 via another wire 500.
The individual electrode 371 makes electrical conduction with the
LED chip 401 via the through wiring 351. The individual electrode
372 makes electrical conduction with the LED chip 402 via the
through wiring 352. The end individual electrode 374 makes
electrical conduction with the LED chip 403 via the corner groove
wiring 342. The end common electrode 375 makes electrical
conduction with the LED chips 401, 402 and 403 via the corner
groove wiring 341.
Light transmitting resin 700 is formed on the main surface 201 of
the substrate 200 and covers the LED chips 401, 402 and 403. The
light transmitting resin 700 is transparent resin such as, epoxy
resin, or resin which is capable of transmitting light from the LED
chips 401, 402 and 403. In this embodiment, the light transmitting
resin 700 has a trapezoidal shape when viewed in the y direction
and a rectangular shape when viewed in the x direction. The light
transmitting resin 700 has, for example, a size of about 0.8 mm in
the z-direction.
Next, operation of the LED module 101 will be described.
According to this embodiment, a path from the individual electrodes
371 and 372 via the through wirings 351 and 352 is used to supply
power to the LED chips 401 and 402. This path does not have a
portion which surrounds the area from the main surface 201 or the
rear surface 202 into the bottom surface 203. Thus, a space to be
secured in the main surface 201 and the rear surface 202 for
forming the wirings 300 may be reduced, thereby achieving
compactness of the LED module 101.
A path from the end individual electrode 374 and the end common
electrode 375 through the corner groove wirings 341 and 342 is used
to supply power to the LED chips 401, 402 and 403. Accordingly, the
bottom surface 203 is not covered with the wirings 300 at all. That
is, there is no portion surrounding the wirings 300 that exists
from the main surface 201 or the rear surface 202 into the bottom
surface 203. Thus, the space to be secured in the main surface 201
and the rear surface 202 for forming the wirings 300 may be further
reduced.
As shown in FIG. 4, the through holes 211 and 212 are separated
from the bottom surface 203 in the y direction. This can prevent
the mounting position of the LED module 101 from being disturbed by
any unintended deformation of the individual electrodes 371 and 372
due to the existence of the through holes 211 and 212.
FIGS. 6 to 13 show LED modules according to other alternate
embodiments of the present disclosure. In these drawings, the same
or similar elements as the first embodiment are denoted by the same
reference numerals.
FIGS. 6 to 9 show an LED module according to a second embodiment of
the present disclosure. An LED module 102 of this embodiment
includes three through holes 211, 212 and 213, three individual
electrodes 371, 372 and 373 and two end common electrodes 375 and
376. The LED module 102 further includes a reflector 710. The LED
module 102 has an x-direction dimension of about 2.0 mm, a
y-direction dimension of about 0.5 mm and a z-direction dimension
of about 0.9 mm. For the purpose of convenience of understanding,
the light transmitting resin 700 is not shown in FIG. 6.
A substrate 200 is formed with the three through holes 211, 212 and
213. Through wirings 351, 352 and 353 (the through wirings 351 and
353 not shown) are formed on the inner sides of these through holes
211, 212 and 213. The individual electrodes 371, 372 and 373 are
connected to the through wirings 351, 352 and 353, respectively.
Three die bonding pads 301, 302 and 303 are formed on a main
surface 201. Three LED chips 401, 402 and 403 are die-bonded to the
die bonding pads 301, 302 and 303, respectively, and make
electrical conduction with the through wirings 351, 352 and 353,
respectively. The through holes 211 and 213 (the through wirings
351 and 353) are disposed above the LED chips 401 and 403,
respectively, as shown in FIG. 6. The through hole 212 (the through
wire 352) is disposed below the LED chip 402, as shown in FIG.
6.
Two bonding pads 311 and 312 are formed on the main surface 201.
The bonding pad 311 is connected to the LED chip 401 by a wire 500.
The bonding pad 312 is connected to the LED chips 402 and 403 by
different wires 500, respectively. The boding pad 311 is connected
to one quadrant-annular portion 321 and makes electrical conduction
with the end common electrode 375 via a corner groove wiring 341.
The boding pad 312 is connected to the other quadrant-annular
portion 321 and makes electrical conduction with the end common
electrode 376 via a corner groove wiring 342.
The reflector 710 is made of, for example, white resin and is
formed on the main surface 201. The reflector 710 has a reflecting
surface 711. The reflecting surface 711 surrounds the LED chips
401, 402 and 403 and reflects light propagating from the LED chips
401, 402 and 403 in the x or y direction toward the z direction.
The z-direction dimension of the reflector 710 is, for example,
about 0.4 mm. A region surrounded by the reflector 710 is filled
with light transmitting resin 700.
This embodiment can also achieve compactness of the LED module 102.
By arranging the LED chips 401, 402 and 403 and the through holes
211, 212 and 213 in the form of a zigzag, it is possible to reduce
the x-direction dimension of the substrate 200.
FIGS. 10 to 13 show an LED module according to a third embodiment
of the present disclosure. An LED module 103 of this embodiment is
different in configuration of wirings 300 in the main surface 201
and the rear surface 202 from the above-described LED module 102.
The LED module 103 has sizes of about 2.7 mm in the x-direction,
about 0.5 mm in the y-direction and about 0.9 mm in the
z-direction. For the purpose of convenience of understanding, the
light transmitting resin 700 is not shown in FIG. 10.
In this embodiment, a die bonding pad 303 is connected to a
quadrant-annular portion 321. The quadrant-annular portion 321 is
connected to a corner groove wiring 342. Rear surface electrodes
370 include an end individual electrode 374. The end individual
electrode 374 is connected to the corner groove wiring 342. A
bonding pad 312 connected to an LED chip 403 by a wire 500 is
connected to a through wiring 353 (not shown) formed in a through
hole 213. The rear surface electrodes 370 also include a rear
surface interconnection wiring 378. The rear surface
interconnection wiring 378 connects the through wiring 353 and an
end common electrode 375. In the main surface 201, a bonding pad
311 is connected to LED chips 401 and 402 by wires 500,
respectively. The bonding pad 311 makes electrical conduction with
the end common electrode 375 via a corner groove wiring 341. This
allows the end common electrode 375 to make electrical conduction
with the LED chip 403 as well as the LED chips 401 and 402. Through
holes 211 and 212 overlap with the LED chips 401 and 402,
respectively, when viewed in the z direction.
This embodiment can also achieve compactness of the LED module 103.
By overlapping the through holes 211 and 212 with the LED chips 401
and 402, respectively, when viewed in the z direction, it is
possible to accelerate compactness of the substrate, that is, the
LED module 103.
The LED module of the present disclosure is not limited to the
above-described embodiments. Detailed configuration of various
components of the LED module of the present disclosure may be
modified in various ways in design.
According to the above embodiments, a path through the through
wirings is used to supply power to the LED chips. This path does
not have a portion rounded from the main surface or the rear
surface into the bottom surface. This may result in reduction of a
space to be secured in the main surface and the rear surface for
forming the wirings, thereby achieving compactness of the LED
module.
While certain embodiments have been described, these embodiments
have been presented by way of example only, and are not intended to
limit the scope of the disclosures. Indeed, the novel methods and
apparatuses described herein may be embodied in a variety of other
forms; furthermore, various omissions, substitutions and changes in
the form of the embodiments described herein may be made without
departing from the spirit of the disclosures. The accompanying
claims and their equivalents are intended to cover such forms or
modifications as would fall within the scope and spirit of the
disclosures.
* * * * *